Introduction

Writing software that works in perfect conditions is easy. It would be nice if we never had to worry about network latency, service timeouts, storage outages, misbehaving applications, users sending bad arguments, security issues, or any of the real-life scenarios we find ourselves in.

Things tend to fail in the following three ways:

• Immediately

• Gradually

• Spectacularly

Immediately is usually the result of a change to application code that causes a service to die on startup or ...